Remove pylearn1 dependency throught pylearn2

Removed pylearn1 depenceies at spots:

dataset-related:
  pylearn2/utils/utlc.py
  pylearn2/datasets/avicenna.py
  pylearn2/datasets/icml07.py
  pylearn2/tests/rbm/test_ais.py

other:
  pylearn2/pca.py
  pylearn2/packaged_dependencies/theano_linear/util.py

For the dataset related dependencies I adopted filetensor.py and utlc.py from pylearn1.

The existing datasets/avicenna.py makes use of it but it does not follow the pylearn2 dataset API.
It should probably be deprecated and removed. But for now it works as before.